High-bandwidth high-gain amplifier

Abstract

A pipelined analog to digital converter comprises a first stage that receives an input voltage, that generates a first sampled digital value and a first residue voltage, and that includes a first amplifier that amplifies the first residue voltage and generates a first amplified residue voltage. A second stage receives the first amplified residue voltage, generates a second sampled digital value and a second residue voltage, and includes a second amplifier that amplifies the second residue voltage. At least one of the first amplifier and the second amplifier comprises a first transistor having a control terminal, a first terminal, and a second terminal, a transimpedance amplifier having an input that communicates with the first terminal of the first transistor, and an output, and an output amplifier having an input that communicates with the output of the transimpedance amplifier, and an output.

1. A pipelined analog to digital converter, comprising:
 a first stage that receives an input voltage, that generates a first sampled digital value and a first residue voltage, and that includes a first amplifier that amplifies said first residue voltage and generates a first amplified residue voltage; and 
 a second stage that receives said first amplified residue voltage, that generates a second sampled digital value and a second residue voltage, and that includes a second amplifier that amplifies said second residue voltage; 
 wherein at least one of said first amplifier and said second amplifier comprises:
 a first transistor having a control terminal, a first terminal, and a second terminal; 
 a transimpedance amplifier having an input that communicates with said first terminal of said first transistor, and an output; and 
 an output amplifier having an input that communicates with said output of said transimpedance amplifier, and an output, and 
 
 wherein said transimpedance amplifier comprises a nested transimpedance amplifier. 
 
   
   
     2. The pipelined analog to digital converter of  claim 1  wherein at least one of said first amplifier and said second amplifier further comprises a first load that communicates with said first terminal of said first transistor. 
   
   
     3. The pipelined analog to digital converter of  claim 1  wherein at least one of said first amplifier and said second amplifier further comprises a current source that communicates with said second terminal of said first transistor. 
   
   
     4. The pipelined analog to digital converter of  claim 1  wherein at least one of said first amplifier and said second amplifier further comprises:
 a second transistor having a control terminal that receives a second amplifier input, a first terminal, and a second terminal that communicates with said second terminal of said first transistor; 
 a differential transimpedance amplifier having a first input that communicates with said first terminal of said first transistor, a second input that communicates with said first terminal of said second transistor, a first output, and a second output; and 
 a differential output amplifier having a first input that communicates with said first output of said differential transimpedance amplifier, a second input that communicates with said second output of said differential transimpedance amplifier, a first output, and a second output. 
 
   
   
     5. The pipelined analog to digital converter of  claim 4  wherein at least one of said first amplifier and said second amplifier further comprises a second load that communicates with said first terminal of said second transistor. 
   
   
     6. A pipelined analog to digital converter, comprising:
 a first stage that receives an input voltage, that generates a first sampled digital value and a first residue voltage, and that includes a first amplifier that amplifies said first residue voltage and generates a first amplified residue voltage; and 
 a second stage that receives said first amplified residue voltage, that generates a second sampled digital value and a second residue voltage, and that includes a second amplifier that amplifies said second residue voltage; 
 wherein at least one of said first amplifier and said second amplifier comprises:
 a first transistor having a control terminal, a first terminal, and a second terminal; 
 a transimpedance amplifier having an input that communicates with said first terminal of said first transistor, and an output; and 
 an output amplifier having an input that communicates with said output of said transimpedance amplifier, and an output, and 
 
 wherein said output amplifier comprises at least one of an operational amplifier and a telescopic cascaded amplifier. 
 
   
   
     7. The pipelined analog to digital converter of  claim 6  wherein said telescopic cascoded amplifier comprises:
 an input transistor having a control terminal that communicates with said output of said transimpedance amplifier, a first terminal, and a second terminal; 
 an output transistor having a first terminal that communicates with said second terminal of said input transistor, a control terminal, and a second terminal that communicates with said output of said output amplifier; and 
 an output current source with a first terminal that communicates with said second terminal of said output transistor, and a second terminal. 
 
   
   
     8. A pipelined analog to digital converter, comprising:
 a first stage that receives an input voltage, that generates a first sampled digital value and a first residue voltage, and that includes a first amplifier that amplifies said first residue voltage and generates a first amplified residue voltage; and 
 a second stage that receives said first amplified residue voltage, that generates a second sampled digital value and a second residue voltage, and that includes a second amplifier that amplifies said second residue voltage; 
 wherein at least one of said first amplifier and said second amplifier comprises:
 a first transistor having a control terminal, a first terminal, and a second terminal; 
 a transimpedance amplifier having an input that communicates with said first terminal of said first transistor, and an output; and 
 an output amplifier having an input that communicates with said output of said transimpedance amplifier, and an output, and 
 
 wherein said output amplifier comprises a push-pull amplifier. 
 
   
   
     9. A pipelined analog to digital converter, comprising:
 a first stage that receives an input voltage, that generates a first sampled digital value and a first residue voltage, and that includes a first amplifier that amplifies said first residue voltage and generates a first amplified residue voltage; and 
 a second stage that receives said first amplified residue voltage, that generates a second sampled digital value and a second residue voltage, and that includes a second amplifier that amplifies said second residue voltage; 
 wherein at least one of said first amplifier and said second amplifier comprises:
 a first transistor having a control terminal, a first terminal, and a second terminal; 
 a transimpedance amplifier having an input that communicates with said first terminal of said first transistor, and an output; 
 an output amplifier having an input that communicates with said output of said transimpedance amplifier, and an output; and 
 a current source that communicates with a voltage source and that supplies current to said first terminal of said first transistor. 
 
 
   
   
     10. The pipelined analog to digital converter of  claim 9  wherein said current source supplies current to said input of said transimpedance amplifier. 
   
   
     11. A pipelined analog to digital converter, comprising:
 a first stage that receives an input voltage, that generates a first sampled digital value and a first residue voltage, and that includes a first amplifier that amplifies said first residue voltage and generates a first amplified residue voltage; and 
 a second stage that receives said first amplified residue voltage, that generates a second sampled digital value and a second residue voltage, and that includes a second amplifier that amplifies said second residue voltage; 
 wherein at least one of said first amplifier and said second amplifier comprises:
 a first transistor having a control terminal, a first terminal, and a second terminal; 
 a transimpedance amplifier having an input that communicates with said first terminal of said first transistor, and an output; and 
 an output amplifier having an input that communicates with said output of said transimpedance amplifier, and an output, 
 
 wherein at least one of said first amplifier and said second amplifier further comprises:
 a second transistor having a control terminal that receives a second amplifier input, a first terminal, and a second terminal that communicates with said second terminal of said first transistor; and 
 a differential transimpedance amplifier having a first input that communicates with said first terminal of said first transistor, a second input that communicates with said first terminal of said second transistor, a first output, and a second output, and 
 
 wherein said differential transimpedance amplifier comprises a nested differential transimpedance amplifier. 
 
   
   
     12. A pipelined analog to digital converter, comprising:
 a first stage that receives an input voltage, that generates a first sampled digital value and a first residue voltage, and that includes a first amplifier that amplifies said first residue voltage and generates a first amplified residue voltage: and 
 a second stage that receives said first amplified residue voltage, that generates a second sampled digital value and a second residue voltage, and that includes a second amplifier that amplifies said second residue voltage; 
 wherein at least one of said first amplifier and said second amplifier comprises:
 a first transistor having a control terminal, a first terminal, and a second terminal; 
 a transimpedance amplifier having an input that communicates with said first terminal of said first transistor, and an output; and 
 an output amplifier having an input that communicates with said output of said transimpedance amplifier, and an output, and 
 
 wherein said differential output amplifier comprises at least one of a differential operational amplifier, a differential telescopic cascaded amplifier, and a differential push-pull amplifier. 
 
   
   
     13. A pipelined analog to digital converter, comprising:
 a first stage that receives an input voltage, that generates a first sampled digital value and a first residue voltage, and that includes a first amplifier that amplifies said first residue voltage and generates a first amplified residue voltage; and 
 a second stage that receives said first amplified residue voltage, that generates a second sampled digital value and a second residue voltage, and that includes a second amplifier that amplifies said second residue voltage; 
 wherein at least one of said first amplifier and said second amplifier comprises:
 a first transistor having a control terminal, a first terminal, and a second terminal; 
 a transimpedance amplifier having an input that communicates with said first terminal of said first transistor, and an output; 
 an output amplifier having an input that communicates with said output of said transimpedance amplifier, and an output; and 
 a first common-mode feedback circuit that communicates with said transimpedance amplifier. 
 
 
   
   
     14. A pipelined analog to digital converter, comprising:
 a first stage that receives an input voltage, that generates a first sampled digital value and a first residue voltage, and that includes a first amplifier that amplifies said first residue voltage and generates a first amplified residue voltage; and 
 a second stage that receives said first amplified residue voltage, that generates a second sampled digital value and a second residue voltage, and that includes a second amplifier that amplifies said second residue voltage; 
 wherein at least one of said first amplifier and said second amplifier comprises:
 a first transistor having a control terminal, a first terminal, and a second terminal; 
 a transimpedance amplifier having an input that communicates with said first terminal of said first transistor, and an output; and 
 an output amplifier having an input that communicates with said output of said transimpedance amplifier, and an output, and 
 
 wherein said output amplifier is directly coupled to said first output of said transimpedance amplifier. 
 
   
   
     15. A pipelined analog to digital converter, comprising:
 a first stage that receives an input voltage, that generates a first sampled digital value and a first residue voltage, and that includes a first amplifier that amplifies said first residue voltage and generates a first amplified residue voltage; and 
 a second stage that receives said first amplified residue voltage, that generates a second sampled digital value and a second residue voltage, and that includes a second amplifier that amplifies said second residue voltage; 
 wherein at least one of said first amplifier and said second amplifier comprises:
 a first transistor having a control terminal, a first terminal, and a second terminal; 
 a transimpedance amplifier having an input that communicates with said first terminal of said first transistor, and an output; and 
 an output amplifier having an input that communicates with said output of said transimpedance amplifier, and an output, and 
 
 wherein said transimpedance amplifier is directly coupled to said first terminal of said first transistor. 
 
   
   
     16. A pipelined analog to digital converter, comprising:
 a first stage that receives an input voltage, that generates a first sampled digital value and a first residue voltage, and that includes a first amplifier that amplifies said first residue voltage and generates a first amplified residue voltage; and 
 a second stage that receives said first amplified residue voltage, that generates a second sampled digital value and a second residue voltage, and that includes a second amplifier that amplifies said second residue voltage; 
 wherein at least one of said first amplifier and said second amplifier comprises:
 a first transistor having a control terminal, a first terminal, and a second terminal; 
 a transimpedance amplifier having an input that communicates with said first terminal of said first transistor, and an output; and 
 an output amplifier having an input that communicates with said output of said transimpedance amplifier, and an output, and 
 
 wherein said transimpedance amplifier is loads said first terminal of said first transistor.